Italy on Wednesday opened the way for a new wave of privatisations as part of its efforts to calm the markets after a three-day run on its shares and bonds.

Measures to encourage the sale of local authority assets and of state holdings in big corporations were among new provisions inserted at the last minute into a €40bn (£35bn) austerity plan aiming at balancing Italy's public accounts by 2014.

The finance minister, Giulio Tremonti, had earlier reacted to concerns about the possibility of Rome being dragged into the eurozone debt crisis with a promise to impose another round of spending cuts by Friday.

His assurance that opposition parties would agree within a matter of days to rally round further austerity measures immediately calmed jittery investors and revealed yet again the respect that Silvio Berlusconi's finance chief has retained with investors during the crisis.

The Milan stock exchange jumped 1.4% to 18765 points following his comments, while the 10-year yield dropped to 5.45%, after touching 6% a day earlier.

But an attempt to extend liberalisation to the legal professions was watered down when it ran into a determined revolt by lawyers and notaries in Berlusconi's governing Freedom People party. Around 80 threatened to bring down the government rather than agree to the abolition of the "ordini", or professional associations, that limit competition and hold up fees.

The liberalising measures appeared, paradoxically, to have been inserted at the insistence of Italy's centre-left opposition. The Democratic party, the biggest opposition group, is more disposed to de-regulation than Berlusconi's, whose membership includes many small business people who fear increased competition.

The government has made Friday evening's crucial division in the lower house of parliament, where it has a narrow majority, a vote of confidence. So, were it to lose, it would have to resign.

With markets still jittery, the former central bank governor and president-designate of the ECB, Mario Draghi, warned the government that, to meet its target, it would have to raise taxes or make further spending cuts. The ratings agency Fitch nevertheless gave the plan a vote of confidence, saying it expected the government to succeed in cutting the deficit.

It said the market turmoil reflected "a crisis of market confidence in the European policy response to the eurozone debt crisis, rather than deteriorating sovereign credit fundamentals". Germany added to the turmoil after its finance minister, Wolfgang Schäuble, refused to support a leaders' summit this weekend to agree plans for a second Greek rescue.

Schäuble wants to give himself the maximum time possible to pursue his plans for greater private investor involvement in the rescue, which could delay matters until September.

The European Central Bank and several EU leaders have argued that forcing private investors to take a cut in the value of their Greek loans would trigger defaults and a mass investor withdrawal from Italy, Spain and possibly Belgium.

Stress tests on EU banks on Friday have already been called a whitewash by critics, who argue they are designed to disguise the depleted resources of Europe's financial institutions.

German state-owned lender Helaba was expected to be one of about 15 banks failed by the European Banking Authority, before it pulled out on Wednesday. It accused the EBA of ignoring complex derivatives as collateral in determining its capital base.

Kenny and others have warned that unless a summit is held on Friday it could have a strong negative impact on financial markets.

Herman Van Rompuy, the president of the European council, has informed ambassadors he intends to hold the summit on Friday evening, and most of the 17 eurozone member states back the decision.

"Markets reacted very badly after eurozone finance ministers could not reach an agreement," an EU diplomat said, referring to a finance ministers' meeting on Monday. "If they cannot agree, we take the fight to the highest level. People are working on a set of conclusions to be agreed."

A senior EU official said the Germans were furious about being "backed into a corner" and were ready to veto a deal.